Authorities said a pickup belonging to a missing Knox County woman was found on the campus of
Kenyon College late Thursday, prompting a lockdown.
Knox County Sheriff's deputies were searching for two women and two children, reported missing from an Apple Valley home on Thursday evening, 10TV News reported.
Tina Herrmann, 32, Stephanie Sprang, 41, and two children, Cody Manerd, 10, and Sarah Manerd, 13, were reported missing.
The relationship between the four was not immediately clear.
Knox County Sheriff's deputies and investigators from the state's Bureau of Criminal Investigation spent several hours searching a house on Apple Valley Road, 10TV's Ashleigh Barry reported.
BCI investigators said there were signs of a struggle inside the home, Barry reported.
A dark purple Ford F-150 that belonged to one of the women was also missing, deputies said.
Kenyon College, in Gambier Ohio, was put on lockdown shortly after 10 p.m. after the pickup was found abandoned at the Brown Family Environmental Center.
An e-mail, sent to students at 11:10 p.m., said law enforcement told college officials there was a "potentially dangerous person in the vicinity."
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